(function () {
  change()

  window.onresize = function () {
    change()
  }

  window.orientationchange = function () {//orientationchange  屏幕旋转事件
    change()
  }


  function change() {
    var winW = document.documentElement.clientWidth || document.body.clientWidth;
    document.documentElement.style.fontSize = winW * 100 / 750 + "px"
    console.log("1rem=" + winW * 100 / 750 + "px")
  }
})()